The adapters fit. I got them put on. I mowed my lawn. I took them back off.
Here are my thoughts so far.
They were made too short by about 1/8".
Here is a picture of the original blades end to end length:
Here is the length of the Razor tri-blade:

I think I see a design flaw here as well. The blade is shorter on the side away from the sharp edge. This means that every time you sharpen the blade it will get shorter, end to end. Maybe not by much but even the 1/8" difference counts.
Here is how I measured them since there isn't a straight across length on the tri-blade. I stuck them on the same spindle bolt and rotated them to be straight across:
Please note that before I got the new adapters I called the company with the concern about the blades being too short and they said they'd make it right, just as they did with the center hole adapter.
As you can see, compared to the OEM blades, the Razor blades are nearly zero-lift:
I found the Razors to throw almost 2 passes. I have a 36" mower so I'd estimate about 60". On the other hand the OEM blades throw just over 5 passes to the right. You can see what I mean by the grass I threw in the street:
I also noticed the Razors don't chop the clippings up as finely. Here are the stock blades (it's a bit wet today so it looks a bit clumpy):
And here are the Razor clippings:
I don't know if the stringers the Razors leave are due to the blades being too short or the lack of lift but here are some pics. It may be hard to see in the pics but it's obvious in person.

You can see the stringers both in the middle and at the ends.
I did notice the blades are quieter but low-lift blades are always quieter than high-lift blades.
I noticed no difference in vibration as all blades were balanced.
All this being said, I'm not going to pass judgment yet. I'm going to give them the chance to honor their deal and make things right. In fact, I'm sending this exact thing to them as soon as I post it.
I'm going to ask everyone to also not yet pass judgment or dismiss this yet. Let's see how it's handled as customer service after the sale is just as important as the product.